1. Field of the Invention
The present invention relates to apparatus used for the repairing, reworking and/or production of electronic components and circuit boards and which use a flow of hot air to re-melt solder retaining the electronic components on a substrate, such as a circuit board. More specifically, the present invention relates to adapters as are used to interchangeably mount various different nozzles to such apparatus.
2. Description of Related Art
In apparatus used for the repairing, reworking and/or production of electronic components and circuit boards, nozzles are used to direct and confine the flow of hot air, used to re-melt solder retaining the electronic components on a circuit board, so that all of the solder connections can be heated simultaneously. However, since electronic components differ widely in size, a different nozzle is needed for each component. Thus, it is necessary for the nozzle of such apparatus to be mounted in a manner which enables it to be exchanged with various other nozzles.
U.S. Pat. Nos. 4,972,990 and 4,899,920 to Abbagnaro et al. disclose an apparatus for removal and installation of electronic components on a substrate, such as a printed circuit board, which has a heater assembly with a plurality of locking pins which serve to retain a nozzle base in position against a bottom end of the heater assembly. A pair of locating pins act in cooperation with one another to secure the nozzle base to the heater assembly by operation of a shear handle. This apparatus is large and is designed to be stationarily placed on a table top or other work surface. In this context, the indicated means by which nozzles are attached and detached is size satisfactory. However, because of the size and number of components which are used and the need to use two hands to mount an dismount a nozzle, such the disclosed nozzle attachment/detachment arrangement is not suitable for apparatus having a handheld instrument for applying hot air for producing solder reflow.
U.S. Pat. No. 5,054,106 to Fortune shows a hot gas soldering system with a handheld instrument for applying hot gas for producing solder reflow. Tips and nozzles of various types and configurations have a nut portion that can be threaded onto the end of the instrument, or in one embodiment, a nut with spring fingers having an inwardly directed retaining shoulder is used to a retain a soldering tip. Other exchangeable tip assemblies for soldering/desoldering tools are shown in Fortune""s U.S. Pat. Nos. 4,686,737 and 4,497,427, the latter mentioned patent also uses a threaded nut as a tip housing, while the former discloses the use of annular ridges or threads on an outer surface of a body portion of a removable end cap for retaining various tips or nozzles on the end of a handheld desoldering tool. However, such attachment arrangements make it difficult to maintain the correct radial position of the tip under both cold and hot conditions. In the case of an annular retaining shoulder, the tip is able to shift radially and is always free to rotate, so that maintaining a set position is impossible. On the other hand, with a threaded connection, only one radial position is possible and manufacturing of all nozzles accurately enough to achieve the same relative position is expensive. Moreover, threads can bind easily as a result of thermal cycling.
Thus, there is still a need for an arrangement by which a variety of different nozzles can be quickly and easily be mounted/dismounted to/from apparatus of the type using hot air for soldering/desoldering connections of electrical components for installation and removal thereof with respect to a substrate, such as a printed circuit board. In particular, there is a need for such an arrangement that can be easily and economically produced, and is suitable for use on handheld tools, not merely stationary apparatus.
In view of the foregoing, a primary object of the present invention is to provide an adapter assembly suitable for interchangeably mounting various different nozzles to apparatus which use a flow of hot air to re-melt solder retaining electronic components on a substrate, such as a circuit board, for repairing, reworking and/or production thereof.
More specifically, it is an object of the present invention to obtain foregoing object in a manner applicable to both stationary and handheld heat applying units.
Yet another object is to attain the above objects in a manner that can be easily and economically produced.
Still another object of the present invention is to provide an adapter suitable for interchangeably mounting various different nozzles to apparatus of the noted type that is easy to use, yet assures proper positioning of the nozzles relative to the heater head, and thus, with reference to the component being worked on.
These and other objects of the invention are obtained via a nozzle adaptor which has an internal adapter body which resiliently carries a support collar which is held in an axial direction relative to the internal body by a spring. A bezel ring having a plurality of receiving tabs is mounted in the support collar, the tabs on the bezel ring in the support collar engage tabs on a mounting plate of each nozzle assembly, causing compression of the spring and resulting in a clamping of the mounting plate between a bottom surface of the internal body and the bezel ring.
These and further objects, features and advantages of the present invention will become apparent from the following description when taken in connection with the accompanying drawings which, for purposes of illustration only, a single embodiment in accordance with the present invention.